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Experimental study of the bistable flow in tube arrays
Olinto, Cláudio R.;Indrusiak, Maria Luíza S.;M?ller, Sérgio V.;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2006, DOI: 10.1590/S1678-58782006000200013
Abstract: flow through circular cylinder arrays are commonly found in several engineering application as offshore structures, heat exchangers, transmission lines and chimneys, therefore the understanding of the several phenomena that occur due the interaction between flowing fluid and these structures is very important. this work analyzes experimentally the presence of phenomenon called bistable or biased flow, which is able to cause alternations on the flow modes in cylinder arrays. for the experimental work, two cylinders are placed side-by-side, or forming a tube bank with in line arrangement. the first arrangement corresponds to the case where the phenomenon is easily detected, and in line tube bank, the phenomenon has been also found. the experiments were performed in a wind channel using hot wire anemometry additionally to the classical statistic and spectral tools, wavelet transforms are used. the bistable flow can be an important generator of dynamic instabilities, since it alternates the lift and drag coefficients, thus alternating the structure dynamic response.
Bone Loss at Implant with Titanium Abutments Coated by Soda Lime Glass Containing Silver Nanoparticles: A Histological Study in the Dog  [PDF]
Arturo Martinez, Francisco Guitián, Roberto López-Píriz, José F. Bartolomé, Belén Cabal, Leticia Esteban-Tejeda, Ramón Torrecillas, José S. Moya
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0086926
Abstract: The aim of the present study was to evaluate bone loss at implants connected to abutments coated with a soda-lime glass containing silver nanoparticles, subjected to experimental peri-implantitis. Also the aging and erosion of the coating in mouth was studied. Five beagle dogs were used in the experiments. Three implants were placed in each mandible quadrant: in 2 of them, Glass/n-Ag coated abutments were connected to implant platform, 1 was covered with a Ti-mechanized abutment. Experimental peri-implantitis was induced in all implants after the submarginal placement of cotton ligatures, and three months after animals were euthanatized. Thickness and morphology of coating was studied in abutment cross-sections by SEM. Histology and histo-morphometric studies were carried on in undecalfied ground slides. After the induced peri-implantitis: 1.The abutment coating shown losing of thickness and cracking. 2. The histometry showed a significant less bone loss in the implants with glass/n-Ag coated abutments. A more symmetric cone of bone resorption was observed in the coated group. There were no significant differences in the peri-implantitis histological characteristics between both groups of implants. Within the limits of this in-vivo study, it could be affirmed that abutments coated with biocide soda-lime-glass-silver nanoparticles can reduce bone loss in experimental peri-implantitis. This achievement makes this coating a suggestive material to control peri-implantitis development and progression.
The periodic magnetized cylinder tube for atom guidance: quantized motion analysis
The periodic magnetized cylinder tube for atom guidance: quantized motion analysis

Li Dai-Jun,Zhou Bo,Hu Zheng-Feng,Li Shi-Qun,

中国物理 B , 2003,
Abstract: We have analysed the transport efficiency of an atomic waveguide constructed from a periodic axially magnetized hollow tube. We took into consideration the quantized motion of the atom inside the magnetic hollow cylinder tube, which is significant for the transportation of cold atoms. We deduced the quantized motion modes of the atomic waves in the tube by the approximation of infinite potential, which is valid for cold atoms and strong magnetization. For the atomic waveguide with weak magnetization, we have calculated the tunnelling effect of the atomic wave. The adiabatic condition for the motion of cold atoms is discussed. A time orbit potential method for solving the "zero magnetic field problem" is proposed.
Axial Creeping Flow in the Gap between a Rigid Cylinder and a Concentric Elastic Tube  [PDF]
Shai B. Elbaz,Amir D. Gat
Physics , 2015,
Abstract: We examine transient axial creeping flow in the annular gap between a rigid cylinder and a concentric elastic tube. The gap is initially filled with a thin fluid layer. The study focuses on viscous-elastic time-scales for which the rate of solid deformation is of the same order-of-magnitude as the velocity of the fluid. We employ an elastic shell model and the lubrication approximation to obtain a forced nonlinear diffusion equation governing the viscous-elastic interaction. In the case of an advancing liquid front into a configuration with a negligible film layer (compared with the radial deformation of the elastic tube), the governing equation degenerates into a forced porous medium equation, for which several closed-form solutions are presented. In the case where the initial film layer is non-negligible, self-similarity is used to devise propagation laws for a pressure driven liquid front. When advancing external forces are applied on the tube, the formation of dipole structures is shown to dominate the initial stages of the induced flow and deformation regimes. These are variants of the dipole solution of the porous medium equation. Finally, since the rate of pressure propagation decreases with the height of the liquid film, we show that isolated moving deformation patterns can be created and superimposed to generate a moving wave-like deformation field. The presented interaction between viscosity and elasticity may be applied to fields such as soft-robotics and micro-scale or larger swimmers by allowing for the time-dependent control of an axisymmetric compliant boundary.


物理学报 , 1990,
Abstract: The theoretical analysis and experimental result of steady-state thermal distortion in hollow cylinder lasers are given in this paper. The basic considerations of a 1 kW average power Nd: glass hollow cylinder laser are presented.
Microwave Scattering and Absorption by a Multilayered Lossy Metamaterial --- Glass Cylinder
Juozas Bucinskas;Liudmila Nickelson;Viktoras Shugurovas
PIER , 2010, DOI: 10.2528/PIER10041711
Abstract: Here we present the rigorous electrodynamical solution of diffraction problem about the microwave scattering by a multilayered cylinder. The number and thickness of layers is not limited. We offer the solution when the central core of multilayered cylinder can be made of different isotropic materials as a metamaterial, a ceramic matter or a semiconductor as well as of a perfect metal. The isotropic coated layers can be of strongly lossy materials. The signs of the complex permittivity and the complex permeability can be negative or positive in different combinations. Here we present dependencies of the scattered power of the incident perpendicularly and parallel polarized microwaves by the metamaterial-glass cylinder on signs of metamaterial permittivity as well as permeability. Here are also presented the glass layer absorbed power and the metamaterial core absorbed power dependent on the hypothetic metamaterial permittivity and permeability signs at the wide range frequencies 1-120 GHz. The metamaterial core of cylinder has a radius equal to 0.0018 m and the thickness of the coated acrylic-glass layer is 0.0002 m. We have found some conditions when the scattered-power has minimal values and the absorbed power by the coated acrylic glass layer is constant in a very wide frequency range. We have discovered that the glass layer absorbed power decreases with increasing of the frequency at the range 1-120 GHz for both microwave polarizations.
The periodic magnetic cylinder tube for atom guidance: transport efficiency analysis
The periodic magnetic cylinder tube for atom guidance: transport efficiency analysis

Li Dai-Jun,Hu Zheng-Feng,Li Shi-Qun,

中国物理 B , 2003,
Abstract: We have proposed a model of periodic axial magnetized hollow tube for atom guidance (1999 Opt. Commun. 160 72-4). In the present paper, an analytic solution of the magnetic field inside the tube is obtained and the transport efficiency of the cold atoms in the magnetic tube at different tube intensities of magnetization is discussed. The effect of the curvature of magnetic tube on the atom transport efficiency is also considered. We have found that the tube has a cooling effect on the transverse temperature of the transported atoms.
Visualized study of the flow field and temperature field in the all-glass evacuated solar collector tube

ZHONG Jian-li,Fu Li-xia,LEI Jin-bo,

浙江大学学报(农业与生命科学版) , 2005,
Abstract: In this article the FLUENT compute model of all-glass evacuated solar collector tube is constructed according to a physical model and the interface of FLUENT. The boundary conditions are established on the basis of the data of three different states of water stagnation. The calculation results have a good match with the test results. By FLUENT, we can graphically observe the variation in fluid field and temperature field during covered solarization of solar collector tube and obtain the data of heat loss by different ways.
Incarcerated Femoral Hernia Containing Ipsilateral Fallopian Tube
Stefanos Atmatzidis,Grigorios Chatzimavroudis,Dimitrios Dragoumis,Konstantinos Atmatzidis
Case Reports in Medicine , 2010, DOI: 10.1155/2010/741915
Abstract: Femoral hernias are more common in women and lead to a substantial higher rate for an emergency operation, due to strangulation. Incarcerated femoral hernia with fallopian tube as a content is an extremely rare condition. A 20-year-old woman presented to the emergency department complaining of a 6-day right groin swelling, which became painful and tender to palpation during the last 48 hours. Preoperative ultrasonography detected an oedematous hernia sac, above the femoral vessels, suggesting the presence of an incarcerated femoral hernia. The patient eventually underwent emergency surgery and the diagnosis of a strangulated femoral hernia sac, containing fallopian tube, was established. No resection of the uterine tube was performed and the hernia was repaired with polypropylene plug. The postoperative period was uneventful and the woman was discharged on the second postoperative day.
Physical Characteristics and Technology of Glass Foam from Waste Cathode Ray Tube Glass  [PDF]
G. Mucsi,B. Cs?ke,M. Kertész,L. Hoffmann
Journal of Materials , 2013, DOI: 10.1155/2013/696428
Abstract: This paper deals with the laboratory investigation of cathode-ray-tube- (CRT-) glass-based glass foam, the so-called “Geofil-Bubbles” which can be applied in many fields, mainly in the construction industry (lightweight concrete aggregate, thermal and sound insulation, etc.). In this study, the main process engineering material properties of raw materials, such as particle size distribution, moisture content, density, and specific surface area, are shown. Then, the preparation of raw cathode ray tube glass waste is presented including the following steps: crushing, grinding, mixing, heat curing, coating, and sintering. Experiments were carried out to optimize process circumstances. Effects of sintering conditions—such as temperature, residence time, and particle size fraction of green pellet—on the mechanical stability and particle density of glass foam particles were investigated. The mechanical stability (abrasion resistance) was tested by abrasion test in a Deval drum. Furthermore, the cell structure was examined with optical microscopy and SEM. We found that it was possible to produce foam glass (with proper mechanical stability and particle density) from CRT glass. The material characteristics of the final product strongly depend on the sintering conditions. Optimum conditions were determined: particle size fraction was found to be 4–6?mm, temperature 800°C, and residence time 7.5?min. 1. Introduction The corresponding law regulation which came into force in 2004 divides the electric and electronic equipment into ten categories. Those categories in which cathode ray tube (CRT) is mainly applied (consumer electronics and IT) form a significant fraction (nearly 30%) of the electronic waste. Recycling of the scrap CRT poses a special problem. There is no public demand for CRT devices any more; accordingly there is no CRT recycling capacity in Europe and there are barely recycling opportunities outside of Europe. Managing this problem is critical from the viewpoint of functional WEEE treatment systems. The volume rate of the waste CRT devices based on the estimations of Bay Zoltán Nonprofit Ltd.: in the IT category is about 31% and in the consumer electronic category is about 41% of the total annual amount. There is no demand for raw material glass with lead content because there is no CRT manufacturer in Europe. Recycling of CRTs is great problem all over Europe as the arising volume of the CRT glass waste is 400000 tons annually and only few practical and economic solutions are found for recycling. There are two kinds of cathode ray tubes: black and
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